Help needed with GSA panniers

[Coala]

I am looking at getting some alu panniers for my GSA, but aftermarket ones.  Question is whether I should get two different sizes, one left and one right (to compensate for the exhaust), or same size and then have the bike wider on one side.  I intend to use the existing GSA brackets and just adjust it to fit the panniers. What sizes are recommended in terms of liters.  33 for one side and 38 for the other ?  Would that be OKAY and how would it look?   

 

[pierredb]

 

[Adventurer]

 

[luke]

 

[michnus]

 

[luke]

 

[Coala]